Credit cards and debit cards normally have a magnetic stripe adjacent one edge thereof and this magnetic stripe stores certain information with respect to the card. Some of these cards also include an integrated circuit (IC) chip which is embedded in the plastic card. A card of this type is commonly referred to as a "Smart card". The integrated circuit allows for the storage of additional information and in addition to allowing reading of information contained in the chip, it also allows information to be written to the chip. In this way, the card can be updated.
There are a number of different arrangements for reading of magnetic stripe cards from manual readers to automated readers. Perhaps the most common reader is a "swipe" reader where the card is manually forced through a card slot past a magnetic read head. The motion of sliding or swiping the card past a magnetic read head allows the read head to read information contained on the magnetic stripe. Accurate reading of the information most commonly occurs when the card is guided at constant velocity past the read head or is moved past the read head without sudden changes. For example, the card can be accelerating past the read head and as long as the acceleration is generally smooth, accurate reading of the card can occur. Problems occur when there is a sudden change in the velocity or acceleration of the card.
To overcome the problems associated with "swipe" readers, a number of manual and motor-driven systems have been proposed. In such systems, the card is inserted into a slot to an operating position where the read head is driven along the magnetic stripe. Motorized arrangements include some sort of carriage or drive arrangement for moving the head relative to the stripe at essentially constant velocity for reading of information. These types of systems work well and the only major drawbacks are with respect to cost and higher maintenance due to the higher degree of mechanization.
A number of manual readers use some sort of spring biasing means having one end connected to a movable carriage and the other end of the spring connected to the support housing. Potential energy is developed in the spring as the carriage is moved from an initial position to a second position when the card is fully inserted into the device. The carriage is then released and moves over the card and along the magnetic stripe. These systems have not proven entirely satisfactory and are limited by the extent of relative movement of the carriage.
A further type of card reader is known as "a dip" reader. In this structure, the card is fully inserted into a slot and the reading step is carried out when the card is removed from the device. Some people believe it is easier to smoothly remove the card from the device rather than swipe it past a magnetic head. These type of readers suffer from the same problems as "swipe" readers.
Example of various card readers are disclosed in the following U.S. Patents: U.S. Pat. No. 4,833,310; U.S. Pat. No. 4,048,476; U.S. Pat. No. 4,423,320; U.S. Pat. No. 4,575,703; U.S. Pat. No. 3,976,858; U.S. Pat. No. 4,581,523; U.S. Pat. No. 3,940,796; U.S. Pat. No. 3,866,827; and, U.S. Pat. No. 4,529,872.
U.S. Pat. No. 4,529,872, in particular, describes a magnetic card reader for reading signals recorded on the magnetic stripe of a card. The reading head is mounted on a supporting body contained within a housing and the card is inserted through a slot in the housing to engage a stop on the supporting body. The stop and the supporting body are moved against the force of a spiral spring until the supporting body reaches an end position within the housing where the stop engages a counterstop to lower the stop beneath the magnetic card. The supporting body thereby is released for return movement in response to the force of the spring and the magnetic stripe on the card is read during the return movement.